You were born with every egg that you’ll ever have. Although studies suggest that there may be a process where we can create eggs; such technology is far into the future. More importantly, you’re losing eggs at a rate that far exceeds what you would guess. Current research suggests that most women will lose about 500 to 1000 eggs per month through a process of attrition called apoptosis—yet only one or two eggs each month will be capable of fertilization. A recent summary of all of the available research has shown that most women will only have about 3% of their eggs remaining by age 40.

Although the slope of that curve appears intimidating, the goal of this blog post is to increase your awareness and to empower you to take action. Some women are born with more eggs than others. Some women will lose their eggs at a faster rate. Most importantly, the eggs that remain in your ovaries at any given moment represent your ovarian reserve. Therefore, it is very relevant for you to consider how many eggs you have now and then plan how many (more) children you think you might someday wish to have.

This diagram shows the various stages of egg development summarized in a single ovary.

It takes an egg several months to develop from its status as a primordial follicle to that of a mature fertilizable oocyte. It is only when they reach that stage that the ovary releases the egg through a process called ovulation. Fewer than 300 of your eggs are likely to ever complete this journey. In other posts on this blog, we focus on various steps you can take to optimize the health of your developing eggs; but for now let’s focus on the future of your fertility in the months and years to come.

At least 99% of your remaining eggs are dormant—alive but not metabolically active. They have been in this resting state since you were a newborn. The eggs that are in these intermediate stages of development—which represents your fertility—can be estimated by a simple well timed blood test. Consider having your ovarian reserve tested today. Then think about how many children you envision yourself having. Consider when you will be ready to start or expand your family. By doing so, you can better estimate whether or not egg freezing or embryo banking (creating and storing embryos for future use) are steps you should be considering to assist you in creating your future family.

We’re all frightened by what we don’t understand. Many infectious diseases feed in to that fear. Consider for example the recent media frenzy over Ebola Virus; then again over Bird Flu and then more recently over Chikungunya—all of which have died down without the nightmare scenarios coming to fruition. Now we’re focusing on Zika virus. This is admittedly scary due to its possible link to birth defects in babies born in Brazil. So let’s review what we know, what we don’t know AND what we can do in the meantime.

Recently the Society of Maternal-Fetal-Medicine held a special session to review this important topic and provide updated advice and guidance for women’s healthcare specialists in the USA. Zika is a virus transmitted by mosquitos. Those developing a symptomatic infection during pregnancy may be at high risk of having a child with a birth defect known as microcephaly. Although this link has not yet been definitively established it is recommended that we provide very close surveillance of any suspected cases while additional information is gathered. Although this sounds scary here are some of the key facts to keep in mind:

Only 1 in 5 people bitten by an infected mosquito is likely to develop an infection

Those infected have pretty specific symptoms including sore joints, a rash and conjunctivitis (red, swollen areas around the eyes)

The infection will appear within one or two weeks of the mosquito bite

The current test available is nonspecific and can create concerns due to false-positive results (a positive test due to a related virus that has not been linked with birth defects)

The Center for Disease Control and Prevention is monitoring places in the world known to have active Zika transmission for travelers and advising those that are pregnant or planning pregnancy to avoid traveling to those locations

Meanwhile, alternate causes of the fetal malformations are being investigated including a possible link to an insecticide widely used to control mosquitos in the area of Brazil most heavily effected by fetal microcephaly

Clearly we need to learn more about the Zika virus. In the meantime, here is some practical advice for patients that want to become pregnant:

If possible avoid traveling to areas effected by Zika for at least one month prior to starting fertility treatment

During mosquito season (as well as while traveling to effected areas) consider the following protective steps

Wear long sleeves when possible and stay in air conditioned facilities (rather than using open windows for cooling

Use insect repellants to reduce the risk of mosquito bites. Here are two that are among the safest (and least toxic) for women trying to conceive: